Keep an Eye Out for Cereal Leaf Beetle Larvae

Cereal leaf beetle (CLB) adults have been active and laying eggs over the last month in winter cereals. Though the adult feeding does not cause much injury, expect to start seeing larvae and their leaf feeding start over the next few weeks. My crew just found a few first instar CLB larvae today in one of the YEN sites we are monitoring this year. On the positive side, with this heat, the winter cereals are advancing quickly and may get passed the critical early heading stages, avoiding peak larval feeding. But spring cereals might be at greater risk.

Cereal leaf beetle larvae are 6 mm (1/4 in.) in length when mature and yellowish in colour, but this colour is hidden by a black deposit of their fecal material making it slug-like in appearance. This creates a dome around them, keeping them moist in dry conditions while protecting them from predators.  When this outer coating is removed, you will find a yellowish beige larva underneath with a brown head and three pairs of small brown legs at the front of the body.